Adsorbents
Egg Shells of Dromaius novaehollandiae (DNES) were collected from the poultry processing facilities of Bapatla, Andhra Pradesh, India. Shells were washed several times with deionized water to remove dirt particles. The eggshells were then ground to powder, sieved using British Standard Sieves (BSS) into particle size of 53 µm (chosen from different particle sizes tested) for use as sorbent without any pretreatment. Chitosan (prepared from Agaricus bisporus) was purchased from Sigma Aldrich (740179). DNES–CH composite was prepared by first dissolving CH and DNES separately in 10 and 2 % aqueous acetic acid respectively. Further eggshells were treated with 2 % NaHCO3 for neutralisation. Then the neutralized DNES solution was added to CH solution and the mixture was dropped into an alkaline coagulant solution (H2O:MeOH:NaOH = 5:4:1 w/w). The DNES–CH (5:1) composite thus obtained was washed with distilled water and stored for experimental use.